lib/crc: x86: Migrate optimized CRC code into lib/crc/

Move the x86-optimized CRC code from arch/x86/lib/crc* into its new
location in lib/crc/x86/, and wire it up in the new way.  This new way
of organizing the CRC code eliminates the need to artificially split the
code for each CRC variant into separate arch and generic modules,
enabling better inlining and dead code elimination.  For more details,
see "lib/crc: Prepare for arch-optimized code in subdirs of lib/crc/".

Reviewed-by: "Martin K. Petersen" <martin.petersen@oracle.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: "Jason A. Donenfeld" <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20250607200454.73587-12-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>

Author: Eric Biggers

arch/x86/Kconfig

@@ -79,9 +79,6 @@ config X86
 	select ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
 	select ARCH_HAS_CPU_FINALIZE_INIT
 	select ARCH_HAS_CPU_PASID		if IOMMU_SVA
-	select ARCH_HAS_CRC32
-	select ARCH_HAS_CRC64			if X86_64
-	select ARCH_HAS_CRC_T10DIF
 	select ARCH_HAS_CURRENT_STACK_POINTER
 	select ARCH_HAS_DEBUG_VIRTUAL
 	select ARCH_HAS_DEBUG_VM_PGTABLE	if !X86_PAE

arch/x86/lib/Makefile

@@ -40,16 +40,6 @@ lib-$(CONFIG_RANDOMIZE_BASE) += kaslr.o
 lib-$(CONFIG_FUNCTION_ERROR_INJECTION)	+= error-inject.o
 lib-$(CONFIG_MITIGATION_RETPOLINE) += retpoline.o
 
-obj-$(CONFIG_CRC32_ARCH) += crc32-x86.o
-crc32-x86-y := crc32.o crc32-pclmul.o
-crc32-x86-$(CONFIG_64BIT) += crc32c-3way.o
-
-obj-$(CONFIG_CRC64_ARCH) += crc64-x86.o
-crc64-x86-y := crc64.o crc64-pclmul.o
-
-obj-$(CONFIG_CRC_T10DIF_ARCH) += crc-t10dif-x86.o
-crc-t10dif-x86-y := crc-t10dif.o crc16-msb-pclmul.o
-
 obj-y += msr.o msr-reg.o msr-reg-export.o hweight.o
 obj-y += iomem.o
 

lib/crc/Kconfig

@@ -54,6 +54,7 @@ config CRC_T10DIF_ARCH
 	default y if ARM64 && KERNEL_MODE_NEON
 	default y if PPC64 && ALTIVEC
 	default y if RISCV && RISCV_ISA_ZBC
+	default y if X86
 
 config CRC32
 	tristate
@@ -76,6 +77,7 @@ config CRC32_ARCH
 	default y if RISCV && RISCV_ISA_ZBC
 	default y if S390
 	default y if SPARC64
+	default y if X86
 
 config CRC64
 	tristate
@@ -90,6 +92,7 @@ config CRC64_ARCH
 	bool
 	depends on CRC64 && CRC_OPTIMIZATIONS
 	default y if RISCV && RISCV_ISA_ZBC && 64BIT
+	default y if X86_64
 
 config CRC_OPTIMIZATIONS
 	bool "Enable optimized CRC implementations" if EXPERT

lib/crc/Makefile

@@ -17,6 +17,7 @@ crc-t10dif-$(CONFIG_ARM) += arm/crc-t10dif-core.o
 crc-t10dif-$(CONFIG_ARM64) += arm64/crc-t10dif-core.o
 crc-t10dif-$(CONFIG_PPC) += powerpc/crct10dif-vpmsum_asm.o
 crc-t10dif-$(CONFIG_RISCV) += riscv/crc16_msb.o
+crc-t10dif-$(CONFIG_X86) += x86/crc16-msb-pclmul.o
 endif
 
 obj-$(CONFIG_CRC32) += crc32.o
@@ -29,13 +30,16 @@ crc32-$(CONFIG_PPC) += powerpc/crc32c-vpmsum_asm.o
 crc32-$(CONFIG_RISCV) += riscv/crc32_lsb.o riscv/crc32_msb.o
 crc32-$(CONFIG_S390) += s390/crc32le-vx.o s390/crc32be-vx.o
 crc32-$(CONFIG_SPARC) += sparc/crc32c_asm.o
+crc32-$(CONFIG_X86) += x86/crc32-pclmul.o
+crc32-$(CONFIG_X86_64) += x86/crc32c-3way.o
 endif
 
 obj-$(CONFIG_CRC64) += crc64.o
 crc64-y := crc64-main.o
 ifeq ($(CONFIG_CRC64_ARCH),y)
 CFLAGS_crc64-main.o += -I$(src)/$(SRCARCH)
 crc64-$(CONFIG_RISCV) += riscv/crc64_lsb.o riscv/crc64_msb.o
+crc64-$(CONFIG_X86) += x86/crc64-pclmul.o
 endif
 
 obj-y += tests/

arch/x86/lib/crc-pclmul-consts.h lib/crc/x86/crc-pclmul-consts.harch/x86/lib/crc-pclmul-consts.h renamed to lib/crc/x86/crc-pclmul-consts.h

@@ -5,36 +5,24 @@
  * Copyright 2024 Google LLC
  */
 
-#include <linux/crc-t10dif.h>
-#include <linux/module.h>
 #include "crc-pclmul-template.h"
 
 static __ro_after_init DEFINE_STATIC_KEY_FALSE(have_pclmulqdq);
 
 DECLARE_CRC_PCLMUL_FUNCS(crc16_msb, u16);
 
-u16 crc_t10dif_arch(u16 crc, const u8 *p, size_t len)
+static inline u16 crc_t10dif_arch(u16 crc, const u8 *p, size_t len)
 {
 	CRC_PCLMUL(crc, p, len, crc16_msb, crc16_msb_0x8bb7_consts,
 		   have_pclmulqdq);
 	return crc_t10dif_generic(crc, p, len);
 }
-EXPORT_SYMBOL(crc_t10dif_arch);
 
-static int __init crc_t10dif_x86_init(void)
+#define crc_t10dif_mod_init_arch crc_t10dif_mod_init_arch
+static inline void crc_t10dif_mod_init_arch(void)
 {
 	if (boot_cpu_has(X86_FEATURE_PCLMULQDQ)) {
 		static_branch_enable(&have_pclmulqdq);
 		INIT_CRC_PCLMUL(crc16_msb);
 	}
-	return 0;
 }
-subsys_initcall(crc_t10dif_x86_init);
-
-static void __exit crc_t10dif_x86_exit(void)
-{
-}
-module_exit(crc_t10dif_x86_exit);
-
-MODULE_DESCRIPTION("CRC-T10DIF using [V]PCLMULQDQ instructions");
-MODULE_LICENSE("GPL");